Question

我正在尝试从drawable获取位图我使用此代码，但它无法正常工作，因为我无法在静态中使用上下文

这是我这堂课的完整代码：

＆＃13;

package com.onazifi.shelf;

import android.content.Context;
import android.content.Intent;
import android.content.res.AssetManager;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.Drawable;

import org.antlr.runtime.BitSet;

import java.io.IOException;
import java.io.InputStream;

public class BookItem {

	private String author;
	private String title;
	private Bitmap image;

	 Context context;

	public BookItem() {
		// TODO Auto-generated constructor stub
	}

	public BookItem(String _author, String _title , Bitmap _image) {
		this.author = _author;
		this.title = _title;
		this.image = _image;
	}

	public String getAuthor() {
		return this.author;
	}

	public void setAuthor(String _author) {
		this.author = _author;
	}

	public String getTitle() {
		return this.title;
	}

	public void setTitle(String _title) {
		this.title = _title;
	}

	public Bitmap getImage() {
		return this.image;
	}

	public void setImage(Bitmap _image) {
		this.image = _image;
	}


	Bitmap _image = BitmapFactory.decodeResource(context.getResources(),
			R.drawable.gbrankhalil2);



	public static final BookItem[] ALL_BOOKS={

        new BookItem("1","test" ,BitmapFactory.decodeResource(context.getResources(),
				R.drawable.gbrankhalil2) )
       

    };
}

＆＃13;

问题出在这里

＆＃13;

BitmapFactory.decodeResource(context.getResources(),
				R.drawable.gbrankhalil2)

＆＃13;

我无法在静态内调用上下文，如何使用位图从静态内部调用drawable

更新：

这是数组列表存在的地方

＆＃13;

public class Library {

	private ArrayList<BookItem> arrayBookItem;
	public static final int AUTHOR = 1;
	public static final int TITLE = 2;
	public static final int IMAGE = 3;

	public static final int RATE = 4;
	public static final int DOWNLOAD_DATE =5;

	public Library() {
		arrayBookItem = new ArrayList<BookItem>();
	}

	public void setColectionBookItem(ArrayList<BookItem> _array) {
		this.arrayBookItem = _array;
	}

	public void addBookItem(BookItem _bi) {
		this.arrayBookItem.add(_bi);
	}

	public ArrayList<ArrayList<BookItem>> groupbyArrayBookItem(int type) {

		BookItem[] books = BookItem.ALL_BOOKS;
		ArrayList<ArrayList<BookItem>> groupList = new ArrayList<ArrayList<BookItem>>();
		String getType = "";
		
		switch (type) {
		case AUTHOR:
			getType = "bookitem.getAuthor()";
			break;
		case TITLE:
			getType = "bookitem.getTitle()";
			break;
			case IMAGE:
				getType = "bookitem.getImage";
				break;
		case DOWNLOAD_DATE:
			getType = "bookitem.getDownloadDate()";
			break;
		case RATE:
			getType = "bookitem.getRate()";
			break;
		default:
			return groupList;
		}

		/*
		 * books is a object of BookItem
		 * bookitem is item for point to list
		 * getType is a string value for set type of grouping
		 * groupbyArrayBookItem return back array of array of items
		 */
		Iterable<Group> groups = 
				from("bookitem").in(books).group("bookitem")
				.by(getType).into("g").select("g");

		for (Group group : groups) {
			ArrayList<BookItem> obj = new ArrayList<BookItem>();
			for (Object Item : group.getGroup()) {
				obj.add((BookItem) Item);
			}
			groupList.add(obj);
		}

		return groupList;
	}
}

＆＃13;

Answer 1

将context传递到constructor，然后使用它。

public BookItem(Context context, String _author, String _title , Bitmap _image) {
    this.context = context;
    this.author = _author;
    this.title = _title;
    this.image = _image;
}

OR

public BookItem(Context context) {
    this.context = context;
}

然后使用它。

BitmapFactory.decodeResource(context.getResources(),
            R.drawable.gbrankhalil2)

在任何活动中调用它。

BookItem item = new BookItem(MainActivity.this, _author, _title, _image);

OR 如果是片段

BookItem item = new BookItem(getContext(), _author, _title, _image);

我想从一个drawable得到Bitmap

1 个答案: